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side by side

Submitted by tw on September 4, 2017 - 6:43pm

I wrote this while sitting on the Cornell arts quad during my daughter’s band rehearsal. The campus symbolized my past, and her future. She was almost as old as I was when my father died. All that led to some writing, and then this.

(Edit: Followed by another version, quite different.)

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Don't waste a good failure

Submitted by tw on August 4, 2017 - 8:58pm

My troubleshooting rules can really help focus on solving a problem, but maybe first you’d like to not solve the problem for a while.

What?

Well, let’s look at a common sequence of events in creative or constructional work of many kinds:

  1. See a problem.
  2. Figure out how to fix it.
  3. Fix it.

That’s pretty instinctual. Can’t really do those out of order. And once you’ve seen the problem, there is often some amount of urgency to get to the fix.

But the next step, if you’re conscientious, is:

4.. read more...

Weber's Troubleshooting Rules

Submitted by tw on April 23, 2017 - 6:16pm

These rules certainly apply to software of all kinds, and electrical engineering, but they are also basic enough to apply to interpersonal issues, group dynamics, etc.

  1. Is it plugged in?
  2. Is it turned on?
  3. Is it working as designed?
  4. What’s changed since it worked?
  5. What don’t you know?
  6. Who haven’t you talked to?
  7. Poke it with a stick.
  8. Simplify!

And a bonus rule:

0. Don’t solve it too soon!

souvenirs

Submitted by tw on March 1, 2015 - 3:32pm

Written February 24, 2014, as I walked to work. A goose was flying overhead. My uncle was dying, and I was thinking about my memories of him, and about how mysterious memory is, and how we create them for each other, and what going away really means. What’s the difference between a memory, a dream, a plan, and the present moment? Sounds like the beginning of a Buddhist joke. read more...

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Mathematical tests for fair dice

Submitted by tw on October 15, 2013 - 1:26pm

My previous post on fair dice focused on some intuitive ideas about die fairness, and the beginnings of a mathematical approach. Now I’d like to describe the tests my die roller does. These are what I’ve settled on so far as a way to get some numbers to describe and compare the fairness of different dice.

The chi-squared test

First off, there’s the chi-squared goodness-of-fit test. This is a test that looks at the deviations in the histogram to get a total number (the chi-squared statistic) that characterizes how far the histogram deviates from ideal. You can also compare the result statistic to a mathematically-determined threshold that will give you a confidence value for the test; a 95% confidence is often chosen.

So hey, that’s great! We can reduce the whole set of results and its histogram to a single number for a given die, and then find out whether that die is fair or not with 95% confidence! Super! Right? read more...